Hand-held hearing screener apparatus

ABSTRACT

A hearing screener apparatus is provided. In one embodiment, the hearing screener comprises a housing, a testing probe and one or microphones mounted with the testing probe. An elastic coupler may be used to suspend the testing probe from the housing. The testing probe may include a shaft and a removable probe tip mounted on the shaft. An ear tip is fitted onto an end of the removable probe tip. The ear tip may have a flexible flange arranged at its end to seal within the ear canal of the patient. The screener allows the testing probe to be manipulated about all axes and may have an isolation body or assembly that acts as the elastic coupler. The elastic coupler provides vibrational noise isolation due to movement of the patient and the user.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation of U.S. application Ser. No.09/285,938 filed Apr. 2, 1999, now U.S. Pat. No. 6,299,584 issued Oct.9, 2001, which is a continuation-in-part of U.S. application Ser. No.08/832,277 filed Apr. 3, 1997, now U.S. Pat. No. 5,954,669 issued Sep.21, 1999. The above-referenced applications and patents are herebyincorporated herein by reference in their entirety.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] Not Applicable

BACKGROUND OF THE INVENTION

[0003] The present invention relates generally to hearing test devicesand more specifically to an infant hearing screener which usesdistortion-product otacoustic emissions (DPOAE) to determine thefunction of the outer hair cells, which is an indication of middle-earfunction. For example, the absence of DPOAE indicates a possible hearingloss.

[0004] The otacoustic emissions produced by a healthy ear are extremelysmall in magnitude. The emissions typically range from −10 db SPL to +20db SPL. Any kind of extraneous noise introduced into the ear canal ormeasurement system can mask these emissions and give a false negativeresponse. The microphone must have a very low internal noise level todiscriminate the emissions from the system noise. All existing equipmentfor testing for DPOAE uses a probe which seals into the ear canal and isattached to the measurement equipment through a cable. This type ofsystem is not practical in an infant screener for several reasons.

[0005] These reasons include the fact that an infant's ear canal is verysmall, and as a result, it can be quite difficult to seal a probe intosuch a small canal. any pull on the probe from the attached cable canbreak the seal or pull the probe out of the canal. In addition, the timerequired to place a probe in the infant's ear canal significantly slowsdown the testing process. Typically, the infant is asleep when thetesting is performed so that movement is minimal. The process of puttingthe probe into the infant's ear canal in a manner so that it stays forthe duration of the test often wakes the infant which, of course makesthe test difficult or impossible to perform.

[0006] While a hand-held screening device alleviates many of the abovediscussed problems, implementation of such a device has inherentproblems which must be overcome to provide an effective hearingmeasurement device. One such problem results from the vibrational noisegenerated by the tester's hand during the testing. This noise istransmitted through the device and into the microphone which preventsaccurate measurements. Holding a conventional probe to the ear canalcreates a noise level that completely masks any emissions that couldotherwise be detected.

[0007] Another problem is the difficulty in achieving a consistent sealto the infant's ear canal. Difficulty in maintaining the seal resultsfrom minor movements of the infant's head and/or the tester's hand.

[0008] Further limitations and disadvantages of conventional andtraditional approaches will become apparent to one of skill in the art,through comparison of such systems with the present invention as setforth in the remainder of the present application with reference to thedrawings.

BRIEF SUMMARY OF THE INVENTION

[0009] The present invention is related to an hearing screener that usesdistortion-product otacoustic emissions (DPOAE) to determine thefunction of the outer hair cells within the middle ear structure. Thefunction of the outer hair cells is an indication of middle-earfunction; the absence of DPOAE indicates a possible hearing loss.

[0010] In one embodiment, the screener is hand-held device that couplesto the infant's ear to perform DPOAE testing. The device creates tonesand administers them to the ear canal through two receivers. Theemissions are then picked up through a low-noise microphone, andanalyzed by a built-in digital signal processor (DSP). The result isdisplayed on a liquid crystal display (LCD) and can be printed byinfrared link to a separate hand-held printer.

[0011] Aspects of the present invention may be found in a hearingscreener apparatus that comprises a housing, a testing probe operativelycoupled to the housing, and one or more microphone(s). In oneembodiment, the microphone has a noise floor substantially similar to anindustry standard microphone when the housing is grasped by a user. Inanother embodiment, the microphone has a noise floor of at leastapproximately 15 dB lower when the housing is grasped by a user thanwhen the testing probe is grasped by a user.

[0012] The microphone(s) may be mounted with the testing probe, forexample, and the testing probe may be vibrationally isolated from thehousing. In one embodiment, the testing probe is elastically coupled tothe housing. In addition, the hearing screener apparatus may furthercomprise an isolation body elastically coupled between the testing probeand the housing. The hearing screener apparatus may also comprise an eartip mounted on the testing probe for acoustically sealing the ear canalof a test subject.

[0013] These and other advantages and novel features of the presentinvention, as well as details of an illustrated embodiment thereof, willbe more fully understood from the following description and drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

[0014]FIG. 1A is a side view in cross-section of an embodiment of thehearing screener arranged in a patient's ear canal.

[0015]FIG. 1B is a side view in cross-section of an embodiment of thehearing screener arranged in a patient's ear canal.

[0016]FIG. 2 is an exploded cross-sectional side view of an embodimentof the present invention.

[0017]FIG. 3 illustrates a cross-sectional side view of an embodiment ofa hearing screener of the present invention.

[0018]FIG. 4A is a cross-sectional view of a portion of the hearingscreener taken along line AA of FIG. 2.

[0019]FIG. 4B is a cross-sectional view of a portion of the hearingscreener taken along line BB of FIG. 2.

[0020]FIG. 5 is a graph illustrating various microphone noise floorlevels of the present invention.

[0021]FIGS. 6 and 7 illustrate another embodiment of the hearingscreener built in accordance with the present invention.

[0022]FIG. 8 is an exploded view of the hearing screener of FIGS. 6 and7.

[0023]FIGS. 9A, 9B and 9C illustrate mounting of an isolation body orassembly onto a housing of the screener in accordance with the presentinvention.

[0024]FIG. 10 illustrates more detail of the isolation body or assemblywherein a cylinder is mounted onto a spring in accordance with thepresent invention.

[0025]FIGS. 11A, 11B and 11C illustrate mounting of a testing probe on aspring of the isolation body or assembly in accordance with the presentinvention.

[0026]FIGS. 12A and 12B illustrate additional detail of a removableprobe tip of the testing probe in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0027] A hearing screener apparatus which uses distortion productotacoustic emissions (DPAOE) to determine the function of the outer haircells, which is an indicator of middle ear function, is provided. Thehearing screener is preferably a hand-held device that couples to aninfant's ear to effectively perform DPAOE testing for possible hearingloss. An embodiment of the screener includes an assembly to maintainsealing contact in the ear canal of the patient as well as isolatingvibrational noise from their microphone assembly caused by the tester.

[0028] Referring now to the figures, FIG. 1A is a side view incross-section of an embodiment of the hearing screener arranged in apatient's ear canal. FIG. 1B is a similar side view of the bearingscreener arranged at a different angle of attack into the patient's earcanal. An embodiment of the hearing screener is referenced generally at100. A patient's ear 105 is also illustrated. The hearing screener 100includes a testing probe indicated at 110. The testing probe 110includes an ear tip 115. The ear tip 115 is arranged at the entrance ofan ear canal 120 as shown in FIGS. 1A and 1B. As illustrated, the eartip 115 includes a curved flange 125 to effectively seal the ear canal120, thus effectively coupling the testing probe 110 of the hearingscreener 100 with the patient's ear 105 so that proper testing can beperformed.

[0029]FIGS. 1A and 1B also include an isolation body 130 and a housing140. Also, a connection 150 is illustrated. The components of thehearing screener 100 are described in more detail below with referenceto FIGS. 2 and 3.

[0030]FIG. 2 illustrates an exploded side view of an embodiment of thehearing screener 100 of 8 the present invention. For clarity, thehousing 140 is not shown in FIG. 2. As discussed above, the hearingscreener 100 includes the testing probe 110, the isolation body 130 anda cylindrical coupling sleeve 160 disposed between the probe 110 and thebody 130.

[0031] Proceeding from left to right in FIG. 2, the hearing screener 100comprises the ear tip 115 having the curved flange 125 to enable propersealing within a patient's ear canal as illustrated in FIGS. 1A and 1Band described above. The curvature of the flange 125 permits the ear tip115 to be arranged at various angles in the patient's ear canal 120 asshown in FIGS. 1A and 1B. This is beneficial when the patient moves orwhen the tester needs to position the screener 100 at the proper anglefor taking accurate readings. The ear tip 115 also includes alongitudinal throughbore 155. The throughbore 155 is dimensioned toaccept a first end 160 of a microphone housing 165. The first end 160 ofthe microphone housing 165 includes a longitudinal cavity 170. Themicrophone housing 165 also includes a recess 175 for receiving amicrophone 180 therein. FIG. 2 illustrates an embodiment in which twomicrophones are used. However, one or more microphones may be used inthe present invention. The microphones 180 are held in the recess 175which is defined by a first shoulder 185 and a second shoulder 190. Theshoulders 185, 190 protect the microphones 180 as well as provide adefined volume in which the microphones 180 may be located. Themicrophone housing 165 also includes a cylindrical second end 195 havinga bore 200. The bore 200 is designed to receive the connection 150 (seeFIG. 1) which preferably includes one or more sound tubes 202 (see FIG.4A) and electrical connectors 204 for transmitting electrical signalsfrom the microphones 180. In addition, the cylindrical second end 195 ofthe microphone housing 165 includes a circumferential notch 205. Thenotch 205 is explained further below with reference to FIG. 3.

[0032] Continuing to the right of FIG. 2, the hearing screener 100 alsoincludes a microphone housing support member 210 having a through hole215 for receiving the second end 195 of the microphone housing 165therethrough. The support member 210 also includes a curved flange 220.The flange 220 acts as a shield to prevent debris from entering thevarious components of the hearing screener 100. The shielding ability isillustrated in more detail in FIG. 3, in which the hearing screener 100is assembled.

[0033] In addition, the cylindrical coupling sleeve 160 is shown in FIG.2. The coupling sleeve 160 has a open interior 230. An L-shaped notch235 having a cavity 240 is also illustrated. A plurality of o-rings 250fit within the L-shaped notch 235 and are seated in the cavity 240. Inaddition, a retaining cap 255 is provided. The retaining cap 255 slipsover the cylindrical second end 195 of the microphone housing 165 asillustrated more filly in FIG. 3 and captures the o-rings 250 by tabs260 formed in the retaining cap 255.

[0034] Also shown in FIG. 2 is the isolation body 130 which has acylindrical bore 270 for receiving the cylindrical coupling sleeve 160therein. The coupling sleeve 160 is held securely in the isolation body130 by set screws 275 which are tightened into threaded holes 280 formedin the isolation body 130. A second set of o-rings 290 is secured to theisolation body 130 by screws 295. The screws 295 bore into the isolationbody 130. Further, the exploded assembly of FIG. 2 is illustrated in anassembled state in FIG. 3.

[0035]FIG. 3 illustrates an assembled embodiment of the hearing screener100 of the present invention wherein like parts are represented by likenumerals. As illustrated, when the components are assembled, the firstend 160 of the microphone housing 165 fits inside the throughbore 155 ofthe ear tip 115. In addition, the microphone housing 165 fits in thethrough hole 215 of the microphone housing support member 210. Inparticular, the second end 195 of the microphone housing 165 passesthrough the support member 210 and the retaining cap 255 so that thecircumferential notch 205 located adjacent the second end 195 of themicrophone housing 165 is exposed past the retaining cap 255. Thus, aretaining clip 300 can be clipped around the second end 195 of themicrophone housing 165 and reside within the circumferential notch 205to secure the testing probe 110 assembly together.

[0036] As illustrated, the o-rings 250 are secured at one end by thecylindrical coupling sleeve 160 and at the other end by the retainingcap 255. In particular, one end of each o-ring 250 is held in the cavity240 of the L-shaped notch 235 of the cylindrical coupling sleeve 160.Another end of each o-ring is held by tabs 260 of the retaining cap 255.The second set of o-rings 290 is also illustrated in a connected statein FIG. 3. The screws 295 hold one end of the o-ring 290 to theisolation body 130. In addition, screws 305 secure the other end of theo-rings 290 to the housing 140. The housing 140 also has a cavity 310and a mounting surface 315. The screws are preferably screwed into themounting surface 315 of the housing 140.

[0037]FIG. 3 schematically illustrates further components of the hearingscreener 100. For example, a digital signal processor 330 is built intothe housing 140. Also an LCD display 335 is arranged in the housing toprovide measurement data as a display to the user. Further, a printer340 may be used to print out data obtained during the hearing testing.The printer 340 is preferably a small infrared type printer. Also, aninfrared connection 345 between the hearing screener 100 and the printer400 is provided. Also operator control 350 are provided on the housing140.

[0038]FIG. 3 illustrates the hearing screener 100 in a position in whichthe longitudinal axes of the components is perpendicular to the housing140. The two sets of o-rings 250, 290 provide free movement about allaxes for the testing probe portion 110 of the screener 100, as well asthe isolation body 130. However, as FIGS. 1A and 1B indicate, thetesting probe 110 can be displaced at an angle relative to the isolationbody 130, which in turn can also be displaced at an angle relative tothe housing 140. Such compound angular displacements advantageouslyprovide manipulation of the hearing screener 100 to facilitate easy useof the device. Such manipulation capability is provided by thearrangement of the o-rings 250, 290. Embodiments of the arrangement forthe o-rings are illustrated in FIGS. 4A and 4B.

[0039] For example, FIG. 4A illustrates a cross-section view of thearrangement of o-rings 250 which connect the microphone housing 165 tothe coupling sleeve 160 within the isolation body 130. FIG. 4A is takenalong section line A-A in FIG. 3. As shown, four o-rings 250 are equallydistributed between coupling sleeve 160 and the second end 195 of themicrophone housing 165. In this manner, the microphone housing 165 isconcentrically suspended within the coupling sleeve 160. As discussedabove, one end of the o-ring 250 is held within the coupling sleeve 160by being captured within the L-shaped notch 235 and residing in therecess 240. The other end of the o-ring 250 is captured by the tab 260,which is part of the retaining cap 255. Also, the coupling sleeve 160 ismaintained within isolation body 130 by the set screws 275. The setscrews 275 are tightened down within the screw holes 280 to secure thesleeve 160 within the isolation body 130.

[0040]FIG. 4B also illustrates the plurality of o-rings 290 distributedbetween the isolation assembly 130 and the housing 140. FIG. 4B is takenalong section line B-B of FIG. 3. As illustrated, six o-rings 290 aremounted by screws 295 which attach to the isolation body 130 and screws305 which attach to the mounting surface 315 of the housing 140. Theisolation body 130 is thus concentrically suspended within the housing140 by the six o-rings 290. As illustrated in FIGS. 4A and 4B, thenumber of o-rings may be chosen for a particular application. Also, theelasticity of the o-rings may be selected for a particular use andresiliency desired. In a preferred embodiment, o-rings of 70 durometerSHORE A provide a sufficient resiliency and feel. However, the numberand elasticity of the o-rings may be chosen depending on the applicationdesired.

[0041] As set forth above, vibrations caused by the user holding ontothe screener apparatus 100 are translated into noise. An advantage ofthe present invention is a dampening of this noise so that it does notinterfere with the measurements being taken. FIG. 5 graphicallyillustrates how this elimination of the vibrational noise isaccomplished.

[0042]FIG. 5 is a graph illustrating microphone noise various curvesplotted for different measurement situations. The Y axis is dB and the Xaxis is frequency in kilohertz (kHz). The various curves illustrateexperimental data taken as different parts of the hearing screener 100are held by a tester. For example, curve A illustrates the microphonenoise floor with the tester holding the ear tip 115 assembly of thehearing screener 100. Thus, the first set of o-rings 250 and the secondset of o-rings 290 are rendered inoperable. Similarly, curve Billustrates the microphone noise floor when the tester holds theisolation assembly 130 of the hearing tester 100. In this situation, thefirst set of o-rings 250 is operable, but the second set of o-rings 290is not. Finally, curve C illustrates a microphone noise floor curve whenthe tester holds the hearing screener 100 by the housing 140 as intendedduring a typical use. Thus, both sets of o-rings 250, 290 are operable.

[0043] As a basic reference, curve D illustrates the microphone noisefor a microphone, such as an ER-10C microphone. The ER-10C microphonehas the same effective noise floor as an industry standard microphone.Thus, FIG. 5 illustrates that the isolation effects of the o-rings 250and 290, along with the arrangement of the preferred embodimentdiscussed above, yields a microphone noise floor virtually identical tothat of the industry standard microphone when the hearing screener 100is held by the housing 140 as illustrated in curve C. Curve Aillustrates that holding the ear tip assembly 115 of the hearingscreener 100 prevents the benefits of the o-rings 250, 290 from beingexploited. As a result, the noise floor is approximately 15 dB more thanthat experienced in curve C.

[0044] Thus, as described above and graphically illustrated in FIG. 5,the first set of o-rings 250 isolate movements of the patient whichcause noise, and the second set of o-rings 290 isolate hand vibrationwhich causes noise. Together, the reduction in noise is sufficient forallowing the hand-held hearing screener 100 of the preferred embodimentdiscussed above to be used for taking accurate measurements ofotacoustic emissions.

[0045]FIGS. 6 and 7 illustrate another embodiment of the hearingscreener 100 built in accordance with the present invention. The hearingscreener 100 includes a housing 140, an isolation body or assembly 130and a testing probe 110. As explained more completely above and below,the isolation body 130 acts as, for example, an elastic coupler thatsuspends the testing probe 110 from the housing 140. As discussed above,testing probe 110 includes ear tip 115.

[0046] The housing 140 includes a keyboard 351 for entry of commands,and a screen 353 for display of data. The screen 353 may be the same asLCD screen 335 discussed above. The housing 140 also includes a serialport 355 (see FIG. 7) for communication of data to a printer (not shown)or to a suitable docking station (not shown) that may be connected to aprinter, for printout of data obtained during the hearing testing. Theserial port 355 may also be used to communicate data directly to apersonal computer.

[0047] Referring to FIG. 7, testing probe 110 includes a removable probetip 357. Probe tip 357 is removed by pressing tabs 359 and 361. Detailsregarding probe tip 357 are discussed below with respect to FIGS. 12Aand 12B.

[0048]FIG. 8 is an exploded view of the hearing screener 100 of FIGS. 6and 7. Testing probe 110 of FIGS. 6 and 7 is comprised of removableprobe tip 357, seal 363, retainer 365 and shaft 367. A port (note shown)of microphone 369 is inserted into shaft 367 and a seal 371 provides anacoustic seal between the microphone 369 and the shaft 367. Uponassembly, microphone 369 rests adjacent an outer surface 373 of shaft367 and is retained by an inner surface 375 of retainer 365. Retainer365 acts as a fulcrom point for tabs 359 and 361 of removable probe tip357. Eartip 115 fits over a nose portion 379 of removable probe 357.

[0049] Isolation body or assembly 130 of FIGS. 6 and 7 is comprised ofsprings 381 and 383 and cylinder 385. Springs 381 and 383 maybeidentical. Isolation body or assembly 130 attaches to housing 140 andtesting probe 110 as discussed below.

[0050]FIGS. 9A, 9B and 9C illustrate mounting of the isolation body orassembly 130 onto the housing 140. FIG. 9A shows housing 140 having amounting extension 387 protruding therefrom. FIG. 9B shows spring 381mounted on the housing 140 via mating engagement of mounting extension387 into a recess 389 (see FIG. 8) of spring 381. Mounting extension 387includes retaining tabs 382 that releasably lock the spring 381 ontomounting extension 387 of the housing 140. FIG. 9C illustrates theassembly of FIG. 9B further mounting cylinder 385 thereon.

[0051]FIG. 10 illustrates more detail of the mounting of cylinder 385onto spring 381. Cylinder 385 includes notches 388 that engage couplers391 of spring 381. Spring 381 is preferably made of an elastomer typematerial. Couplers 391 therefore provide elastic mounting of thecylinder 385 in spring 381.

[0052] Cylinder 385 further includes grooves 393 and 395. Groove 393 ofcylinder 385 receives and engages ring 397 of spring 381, therebymounting and releasably retaining the cylinder 385 on the spring 381.

[0053]FIGS. 11A, 11B and 11C illustrate mounting of the testing probe110 on the spring 383. Similar to spring 381 as discussed above, spring383 includes a recess 399 that matingly engages a mounting extension 401of shaft 367. Shaft 367 includes retaining tabs 403 to releasable lockspring 383 onto the mounting extension 401 of shaft 367. As can be seenin FIG. 11C, spring 383 includes couplers 405 that engage notches 407 ofcylinder 385 (see FIG. 10). Spring 383 further includes ring 409 thatengages groove 395 of cylinder 385, thereby mounting and releasablyretaining spring 383 on cylinder 385.

[0054] The assembly discussed above with respect to FIGS. 9-11 provideselastic coupling of the testing probe 110 to the housing 140 whilepreventing direct contact between the testing probe 110 and the housing140. Such a configuration assists in reducing the transmission ofvibration from the housing 140 to the testing probe 110. Isolationassembly 130 further enables movement of the testing probe 110 relativeto the housing 140 for ease of manipulation during testing, as describedabove. In addition, the testing probe 110 may be moved relative to theisolation assembly 130, and the isolation assembly 130 may be movedrelative to the housing 140, thereby providing further ease ofmanipulation and vibration dampening.

[0055] As discussed above with respect to FIG. 8, microphone 369 ismounted in testing probe 110. Microphone 369 is electrically connectedto suitable circuitry within the housing 140 via ribbon cable 370. Uponassembly, ribbon cable 370 extends through shaft 367, cylinder 385 andmounting extension 387 into the housing 140.

[0056]FIGS. 12A and 12B illustrate additional detail of the removableprobe tip 357. During testing, sound is presented into the ear canal ofa subject via nose portion 379 of the removable probe tip 357, andparticularly through channels 411 in nose portion 379. The sound isgenerated by speakers contained within the housing 140 and transmittedto the channels 411 via flexible sound tubes (not shown) and via fixedtubes 431 and 433 in the shaft 367. Upon assembly, the flexible soundtubes connect to the fixed tubes and extend from the shaft 367, throughcylinder 385 and mounting extension 387 into the housing 140, like theribbon cable 370 discussed above.

[0057] Signals from the ear canal are received by microphone 369 viachannel 413 in nose portion 379 of removable probe tip 357. Thosesignals are transduced by the microphone 369 and transmitted to thehousing 140.

[0058] Channels 411 and 413 of the nose portion 379 of probe tip 357often become clogged with earwax or other debris, which results intesting failure. Consequently, it is desirable that probe tip 357 beremovable from the shaft 367 for cleaning and/or replacement of theprobe tip 357. As mentioned above, probe tip 357 includes tabs 359 and361 for removable engagement of the probe tip 357 on the shaft 367. Moreparticularly, shaft 367 includes protruding members 415 and 417 thatengage slots in the tabs 359 and 361, respectively. The probe tip 357 isremoved from the shaft 367 by depressing portions 419 and 421 of tabs359 and 361, respectively.

[0059] Upon assembly, seal 363 is trapped between an inner surface 423of probe tip 357 and an outer surface 425 of shaft 367. Seal 363includes openings 427 and 429 that acoustically couple the channels 411and 413 respectively, to tubes 431 and 433 in shaft 367. Seal 363 alsoprovides an acoustic seal between the surfaces 423 and 425. Seal 363may, for example, be made of an elastomer type material to conform tothe surfaces 423 and 425.

[0060] While particular elements, embodiments and applications of thepresent invention have been shown and described, it will be understood,of course, that the invention is not limited thereto since modificationsmay be made by those skilled in the art, particularly in light of theforegoing teachings. It is therefore contemplated by the appended claimsto cover such modifications as incorporate those features which comewithin the spirit and scope of the invention.

1. A hearing screener apparatus comprising: a housing; a testing probeoperatively coupled to the housing; and at least one microphone, themicrophone having a noise floor substantially similar to an industrystandard microphone when the housing is grasped by a user.
 2. Thehearing screener apparatus of claim 1 wherein the at least onemicrophone is mounted with the testing probe.
 3. The hearing screenerapparatus of claim 2 wherein the testing probe is vibrationally isolatedfrom the housing.
 4. The hearing screener apparatus of claim 2 whereinthe testing probe is elastically coupled to the housing.
 5. The hearingscreener apparatus of claim 4 further comprising an isolation bodyelastically coupled between the testing probe and the housing.
 6. Thehearing screener apparatus of claim 1 further comprising an ear tipmounted on the testing probe for acoustically sealing the ear canal of atest subject.
 7. The hearing screener apparatus of claim 1 wherein thehearing screener performs DPOAE testing.
 8. A hearing screener apparatuscomprising: a housing; a testing probe operatively coupled to thehousing; and at least one microphone, the at least one microphone havinga noise floor of at least approximately 15 dB lower when the housing isgrasped by a user than when the testing probe is grasped by a user. 9.The hearing screener apparatus of claim 8 wherein the at least onemicrophone is mounted with the testing probe.
 10. The hearing screenerapparatus of claim 9 wherein the testing probe is vibrationally isolatedfrom the housing.
 11. The hearing screener apparatus of claim 9 whereinthe testing probe is elastically coupled to the housing.
 12. The hearingscreener apparatus of claim 11 further comprising an isolation bodyelastically coupled between the testing probe and the housing.
 13. Thehearing screener apparatus of claim 8 further comprising an ear tipmounted on the testing probe for acoustically sealing the ear canal of atest subject.
 14. The hearing screener apparatus of claim 8 wherein thehearing screener performs DPOAE testing.
 15. A hearing screenerapparatus comprising: a housing; a testing probe operatively coupled tothe housing; and at least one microphone mounted with the testing probe,the testing probe being coupled to the housing such that the at leastone microphone is vibrationally isolated from the housing.
 16. Thehearing screener apparatus of claim 15 wherein the testing probe iselastically coupled to the housing.
 17. The hearing screener apparatusof claim 15 wherein the testing probe is vibrationally isolated from thehousing.
 18. The hearing screener apparatus of claim 17 furthercomprising an isolation body elastically coupled between the testingprobe and the housing.
 19. The hearing screener apparatus of claim 15further comprising an ear tip mounted on the testing probe foracoustically sealing the ear canal of a test subject.
 20. The hearingscreener apparatus of claim 15 wherein the hearing screener performsDPOAE testing.
 21. The hearing screener apparatus of claim 15 whereinthe at least one microphone has a noise floor substantially similar toan industry standard microphone when the housing is grasped by a user.22. The hearing screener apparatus of claim 15 wherein the at least onemicrophone has a noise floor of at least approximately 15 dB lower whenthe housing is grasped by a user than when the testing probe is graspedby a user.